Improved iron grinding-flate



tnitmi mes DANIEL HALLADAY ANI) BURTON H. RUGGLES, OF BA'IAVIA,y

. ILLINOIS.

Letters Patent No. 90,531, dated Ma/y 25, 1869.

IMPROVED IRON G-R'INDIN'G-PLATE.

The Scnedule referred to :in these Letters Patent and making part of the same.

To 'whom it may concern.-

Be it known that we, DANIEL HALLADAY and BUR- TON H RUGGLES, of Batavia, in the county of Kane, and State of Illinois, have invented a new and useful Improvement in Iron GrindingPlutes; and we do declare that the following is atl-ue and accurate description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, and being a part of this specification. E

Figure 1 is aperspeetive View of the upper side of the grinding-plate.

Figure 2 is a sectional view of the grinding-plate at the line X X.

Like letters indicate like parts in each figure.

The nature of' this invention relates to an improvement in iron grinding-plates, and consists in constructing them with their upper and under surfaces similarly grooved or serrated, so that the upper and under plates in the mill can be made to take the place-of each other as the grindingsuriaees become worn by use.

In the drawings, A represents an annular under grinding-plate of the usual vconical form, and provided with the serrations or grooves B, the under side of said grinding-plate being provided with similar serrations, as shown at C in iig. 2, the upper plate being a counterpart of the one described.

When the under surface ofthe upper plate and the upper surface of the under plateV become worn from use, the expense of uewplates is avoided by reversing their positions.

Although these plates are principally used for grinding various kinds of grain, they are not designed exclusively for that purpose, but can be used equally well for grinding coffee, spices, and similar products.

What we claim as our invention, and desire to secure by Letters Patent, isl The method of constructing grinding-plates, with -their upper and under surfaces serrated, substantially as described, and for the purposes hereinbefore specified and set forth. Y

DANIEL HALLADAY. Witnesses: BURTON H. RUGGLES.

H. S. SPRAGUE,

H. F. EBERTs. 

